skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: SU-D-201-05: Phantom Study to Determine Optimal PET Reconstruction Parameters for PET/MR Imaging of Y-90 Microspheres Following Radioembolization

Abstract

Purpose: Imaging Y-90 microspheres with PET/MRI following hepatic radioembolization has the potential for predicting treatment outcome and, in turn, improving patient care. The positron decay branching ratio, however, is very small (32 ppm), yielding images with poor statistics even when therapy doses are used. Our purpose is to find PET reconstruction parameters that maximize the PET recovery coefficients and minimize noise. Methods: An initial 7.5 GBq of Y-90 chloride solution was used to fill an ACR phantom for measurements with a PET/MRI scanner (Siemens Biograph mMR). Four hot cylinders and a warm background activity volume of the phantom were filled with a 10:1 ratio. Phantom attenuation maps were derived from scaled CT images of the phantom and included the MR phased array coil. The phantom was imaged at six time points between 7.5–1.0 GBq total activity over a period of eight days. PET images were reconstructed via OP-OSEM with 21 subsets and varying iteration number (1–5), post-reconstruction filter size (5–10 mm), and either absolute or relative scatter correction. Recovery coefficients, SNR, and noise were measured as well as total activity in the phantom. Results: For the 120 different reconstructions, recovery coefficients ranged from 0.1–0.6 and improved with increasing iteration numbermore » and reduced post-reconstruction filter size. SNR, however, improved substantially with lower iteration numbers and larger post-reconstruction filters. From the phantom data, we found that performing 2 iterations, 21 subsets, and applying a 5 mm Gaussian post-reconstruction filter provided optimal recovery coefficients at a moderate noise level for a wide range of activity levels. Conclusion: The choice of reconstruction parameters for Y-90 PET images greatly influences both the accuracy of measurements and image quality. We have found reconstruction parameters that provide optimal recovery coefficients with minimized noise. Future work will include the effects of the body matrix coil and off-center measurements.« less

Authors:
 [1];  [2];  [3];  [4];  [5]
  1. Washington University in Saint Louis, Saint Louis, MO (United States)
  2. Siemens Healthcare Molecular Imaging, Knoxville, TN (United States)
  3. Washington Univ. School of Medicine, Saint Louis, MO (United States)
  4. Siemens Healthcare, New York, NY (United States)
  5. Washington University School of Medicine, Saint Louis, MO (United States)
Publication Date:
OSTI Identifier:
22486640
Resource Type:
Journal Article
Journal Name:
Medical Physics
Additional Journal Information:
Journal Volume: 42; Journal Issue: 6; Other Information: (c) 2015 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0094-2405
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; BETA-PLUS DECAY; BIOMEDICAL RADIOGRAPHY; COMPUTERIZED TOMOGRAPHY; IMAGES; LIVER; MICROSPHERES; NMR IMAGING; PHANTOMS; POSITRON COMPUTED TOMOGRAPHY; RADIOEMBOLIZATION; YTTRIUM 90

Citation Formats

Maughan, N, Conti, M, Parikh, P, Faul, D, and Laforest, R. SU-D-201-05: Phantom Study to Determine Optimal PET Reconstruction Parameters for PET/MR Imaging of Y-90 Microspheres Following Radioembolization. United States: N. p., 2015. Web. doi:10.1118/1.4923913.
Maughan, N, Conti, M, Parikh, P, Faul, D, & Laforest, R. SU-D-201-05: Phantom Study to Determine Optimal PET Reconstruction Parameters for PET/MR Imaging of Y-90 Microspheres Following Radioembolization. United States. https://doi.org/10.1118/1.4923913
Maughan, N, Conti, M, Parikh, P, Faul, D, and Laforest, R. 2015. "SU-D-201-05: Phantom Study to Determine Optimal PET Reconstruction Parameters for PET/MR Imaging of Y-90 Microspheres Following Radioembolization". United States. https://doi.org/10.1118/1.4923913.
@article{osti_22486640,
title = {SU-D-201-05: Phantom Study to Determine Optimal PET Reconstruction Parameters for PET/MR Imaging of Y-90 Microspheres Following Radioembolization},
author = {Maughan, N and Conti, M and Parikh, P and Faul, D and Laforest, R},
abstractNote = {Purpose: Imaging Y-90 microspheres with PET/MRI following hepatic radioembolization has the potential for predicting treatment outcome and, in turn, improving patient care. The positron decay branching ratio, however, is very small (32 ppm), yielding images with poor statistics even when therapy doses are used. Our purpose is to find PET reconstruction parameters that maximize the PET recovery coefficients and minimize noise. Methods: An initial 7.5 GBq of Y-90 chloride solution was used to fill an ACR phantom for measurements with a PET/MRI scanner (Siemens Biograph mMR). Four hot cylinders and a warm background activity volume of the phantom were filled with a 10:1 ratio. Phantom attenuation maps were derived from scaled CT images of the phantom and included the MR phased array coil. The phantom was imaged at six time points between 7.5–1.0 GBq total activity over a period of eight days. PET images were reconstructed via OP-OSEM with 21 subsets and varying iteration number (1–5), post-reconstruction filter size (5–10 mm), and either absolute or relative scatter correction. Recovery coefficients, SNR, and noise were measured as well as total activity in the phantom. Results: For the 120 different reconstructions, recovery coefficients ranged from 0.1–0.6 and improved with increasing iteration number and reduced post-reconstruction filter size. SNR, however, improved substantially with lower iteration numbers and larger post-reconstruction filters. From the phantom data, we found that performing 2 iterations, 21 subsets, and applying a 5 mm Gaussian post-reconstruction filter provided optimal recovery coefficients at a moderate noise level for a wide range of activity levels. Conclusion: The choice of reconstruction parameters for Y-90 PET images greatly influences both the accuracy of measurements and image quality. We have found reconstruction parameters that provide optimal recovery coefficients with minimized noise. Future work will include the effects of the body matrix coil and off-center measurements.},
doi = {10.1118/1.4923913},
url = {https://www.osti.gov/biblio/22486640}, journal = {Medical Physics},
issn = {0094-2405},
number = 6,
volume = 42,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}